Spinal cord protection practices used during endovascular repair of complex aortic aneurysms by the U.S. Aortic Research Consortium.

BACKGROUND

Spinal cord ischemia/infarction (SCI) is a devastating complication of thoracoabdominal aortic aneurysm repair that can result in permanent paresis or paralysis. The reported incidence of SCI after aortic interventions has ranged from 2% to 10%. Methods to prevent SCI are a topic of ongoing research, and many current practices have been based on expert opinion.

METHODS

In an effort to better delineate the best practice models for SCI prevention during endovascular thoracoabdominal aortic aneurysm repair, a 65-question survey was completed by the eight principal investigators of the U.S. Aortic Research Consortium to capture data related to current practices and management strategies related to the prevention and treatment of SCI. Specific categories of interest included considerations for the "high-risk" classification of SCI, current perioperative prevention practices, indications for and management of spinal drains, and SCI rescue maneuvers.

RESULTS

The most common practices routinely included blood pressure elevation (7 of 8; 87.5%), with most having a mean arterial pressure goal of not less than 90 mm Hg in the perioperative period (5 of 7; 71%), a hemoglobin goal intra- and postoperatively of not less than 10 mg/dL (6 of 8; 75%), and the use of prophylactic spinal drains in high-risk patients (6 of 8; 75%). Significant variation was found among the group for the timing of the resumption of antihypertensive medications, duration of hemoglobin goals after the procedure, and management of spinal drains. Many methods described in reported studies were not routinely used by most of the group, including a perioperative steroid bolus (1 of 8; 12.5%), mannitol (2 of 8; 25%), and naloxone infusion (1 of 8; 12.5%). Rescue maneuvers included placement of a cerebrospinal fluid (CSF) drain if not already present (8 of 8; 100%), decreasing the target CSF drain pop-off pressure (6 of 8; 75%), increasing the CSF drainage volume (5 of 8; 62.5%), increasing the mean arterial pressure goal (8 of 8; 100%), increasing the hemoglobin goal (8 of 8; 100%), and imaging the spine using computed tomography or magnetic resonance imaging (7 of 8; 87.5).

CONCLUSIONS

In general, consistent broad practices were used by most of the consortium; however, the details of specific parameters (ie, spinal drain management, therapy duration, and timing of resumption of antihypertensive medication) varied among the group. The U.S. Aortic Research Consortium group used the results of the survey for discussion and agreed on standardized SCI prevention recommendations in accordance with the group's collective expert opinion and experience. Variations in current practice were also identified to act as a foundation for future study, the most notable of which was the comparative effectiveness of therapeutic vs prophylactic use of CSF drains in the prevention of SCI.